The announcement arrives days before the launch of the holiday shopping season. It also comes as Wal-Mart is trying to increase sales in the U.S. and globally amid slower growth and blemishes on its reputation, according to the AP.

Among the challenges McMillon faces is competition from online competitors that offer cheaper prices, stagnant wages for the company’s low-income shoppers, and criticism for its oversight of factory conditions after a building collapsed in Bangladesh and killed at least 1,127 garment workers.

Additionally, allegations surfaced last year of company officials engaging in bribery in Mexico to speed up building permits, among other things. Overseas business has since slowed.

Duke's decision to leave Wal-Mart was "a personal one," and had nothing to do with the bribery allegations, Dave Tovar, a Wal-Mart spokesman, told the AP.

McMillon’s history with the store chain began in the summer of 1984, when he worked as an intern in a distribution center before leaving for the University of Arkansas.

While pursuing his MBA, he rejoined the company in 1990 and spent more than two decades building his career, mostly in merchandising positions.

“A merchant at heart, Doug has both a long history with our company and a keen sense of where our customers globally are heading next,” said billionaire Wal-Mart Chairman Rob Walton in a statement.

“He has also shown strong leadership on environmental sustainability and a commitment to using Walmart’s size and scale to make a difference in the lives of people, wherever they might be.”

The new Wal-Mart CEO is Doug McMillon, who began his career at the company as a teen working in a warehouse. The retail giant announced Monday that McMillon, head of international operations, will succeed current president and CEO Mike Duke.